Panoramic imaging arrangement

ABSTRACT

According to one aspect of the invention there is provided a panoramic imaging arrangement comprising a transparent component and a reflective material. The transparent component has a first surface about a vertical axis of revolution, a second surface about the axis of revolution, and an opening formed therein to define a third, internal surface about the axis of revolution. The third surface has a concave profile in a plane of the axis of revolution. The reflective material is located on the second surface to provide a reflective surface against the second surface. The first surface, the reflective surface and the third surface are positioned relative to one another so that light from a 360° surrounding panoramic scene enters the transparent component through the first surface, whereafter the light is reflected from the reflective surface, whereafter the light exits the transparent component through the third surface.

This is a continuation of co-pending application Ser. No. 09/229,807,filed Jan. 13, 1999, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1). Field of the Invention

This invention relates to a panoramic imaging arrangement of the kindcapable of capturing, focusing, correcting aberrations and otherwisemanipulating light received from a 360° surrounding panoramic scene.

2). Discussion of Related Art

Panoramic imaging arrangements have become popular in recent years forpurposes of viewing 360° surrounding panoramic scenes. Older generationsof panoramic imaging arrangements generally consisted of revolvingperiscope-like constructions having relatively complex mechanisms forrevolving them. More recently, stationary panoramic imaging arrangementshave been developed. A stationary panoramic imaging arrangementgenerally has one or more lenses, each having a vertical axis ofrevolution, which are used to refract or reflect light received from a360° surrounding panoramic scene. The lenses alter the direction of thelight, whereafter the light passes through a series of lenses-which arelocated vertically one above the other and which further manipulate thelight by, for example, focusing the light or altering the intensity ofthe light.

The task of receiving light in a sideways direction and altering thedirection of the light so that the light then proceeds in a verticaldirection is a difficult one. Altering the direction of light to such adegree, especially when coming from a 360° surrounding scene, oftentimesleads to aberrations in the resulting light. These aberrations mayinclude astigmatism of the light, defects in color of the light, a lossof image plane flatness, and other defects, some of which are discussedin more detail herein below.

Relatively complex lenses and lens arrangements have been developed inorder to overcome these aberrations and produce an acceptable image.These lens arrangements usually include a large number of lenses andoftentimes have lenses with surfaces which are aspherical (see forexample U.S. Pat. No. 5,473,474 issued to Powell). Aspherical lenses aredifficult to manufacture and therefore less practical to manufacturethan for example spherical lenses.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided a panoramicimaging arrangement comprising a transparent component and a reflectivematerial. The transparent component has a first surface about a verticalaxis of revolution, a second, substantially spherical, surface about theaxis of revolution, and an opening formed therein to define a third,internal surface about the axis of revolution. The third surface has aconcave profile in a plane of the axis of revolution. The reflectivematerial is located on the second surface to provide a reflectivesurface against the second surface. The first surface, the reflectivesurface and the third surface are positioned relative to one another sothat light from a 360° surrounding panoramic scene enters thetransparent component through the first surface, whereafter the light isreflected from the reflective surface, whereafter the light exits thetransparent component through the third surface.

The first surface may have a convex profile in a plane of the axis ofrevolution and is preferably substantially spherical.

The first surface and the reflective surface are preferably located onopposing sides of the transparent component and the reflective surfacepreferably has a convex profile in plane of the axis of revolution.

Preferably, at least extensions of the first surface and the reflectivesurface intersect one another.

The third surface is preferably substantially spherical.

In one embodiment the first surface, the reflective surface and thethird surface are all substantially spherical and have a radiuses whichare in the relationship of about 21 units for the first surface, about40 units for the reflective surface, and about 7 units for the thirdsurface.

At least extensions of the first surface and the reflective surface mayintersect the axis of revolution at respectively first and secondlocations which may be about 9 units displaced from one another.

At least an extension of the third surface may intersect the axis ofrevolution at a third location which is about 0.5 units displaced fromthe second location.

The panoramic imaging arrangement may further comprise a system oflenses positioned to receive the light after exiting the transparentcomponent, the system of lenses at least focusing the light. The lightis preferably focused in a plane which is substantially flat.

Preferably, the light passes through a total of less than five lensesfrom exiting the transparent component until being focused.

The panoramic imaging arrangement may further comprise a mirror whichreflects the light after exiting the transparent component. A hole maybe formed through the transparent component with the opening forming atleast part of the hole. The light may at least partially pass throughthe hole after being reflected by the mirror and before passing throughthe system of lenses. The mirror may be curved and preferably has aconcave reflective area.

According to a further aspect of the invention a panoramic imagingarrangement is provided comprising a transparent component and areflective material. The transparent component has first and secondsurfaces, both about a vertical axis of revolution. The first surfacehas a convex profile in a plane of the axis of revolution. The secondsurface has a concave profile in a plane of the axis of revolution. Atleast extensions of the first and second surfaces intersect one another.The reflective material is located on the second surface to provide areflective surface against the second surface. The first surface and thereflective surface are positioned relative to one another so that lightfrom a 360° surrounding panoramic scene enters the transparent componentthrough the first surface, whereafter the light is reflected from thereflective surface.

The second surface may be substantially spherical.

BRIEF DESCRIPTION OF THE DRAWING

The invention is further described by way of example with reference tothe accompanying drawing which is a sectioned side view of a panoramicimaging arrangement, according to an embodiment of the invention, in aplane of a vertical axis of revolution thereof.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 of the accompanying drawings illustrates a panoramic imagingarrangement 10, according to an embodiment of the invention, in a planeof a vertical axis of revolution 12 thereof. The panoramic imagingarrangement 10 includes a lens block 14, a mirror 16, and a system oflenses 18.

The lens block 14 includes a transparent component 20 having a first,upper, convex surface 22 symmetrically about the axis of revolution 12and a second, lower, concave surface 24 also symmetrically about theaxis of revolution 12. A reflective material 26 is formed on the lower,concave surface 24. A hole 28 is formed vertically through thetransparent component 20.

The upper, convex surface 22 of the transparent component 20 isspherical and has a radius of about 21.310 mm. An extension of theupper, convex surface 22 intersects the axis of revolution 12 and afirst location 32.

The lower, concave surface 24 of the transparent component 20 isspherical and has a radius of about 40.200 mm. Extensions of the upper,convex surface 22 and of the lower, concave surface 24 intersect oneanother due to the larger radius of the lower, convex surface 24 withrespect to the radius of the upper, convex surface 22. An extension ofthe lower, concave surface 24 intersects the axis of revolution 12 and asecond location 36 which is located about 9 mm below the first location32 where the extension of the upper, convex surface 22 intersects theaxis of revolution 12.

By forming the reflective material 26 on the lower, concave surface 24,the reflective material 26 provides a concave reflective surface 38against the lower, concave surface 24 and conforming in shape thereto.

An upper portion of the hole 28 is formed by an opening defining athird, internal surface 40 of the transparent component 20. The internalsurface 40 is located symmetrically about the axis of revolution 12. Theinternal surface 40 is spherical and has a concave profile with a radiusof about 7.650 mm. An extension of the internal surface 40 intersectsthe axis of revolution 12 at a third location 44 which is located about0.5 mm above the second location 36 where the extension of the lower,concave surface 24 (and therefore also of the reflective surface 38)intersects the axis of revolution 12.

The mirror 16 is secured to the transparent component 20 at a locationover the hole 28. The mirror 16 has a concave reflective area 46 whichis spherical and is located symmetrically about the axis of revolution12. The reflective area 46 has a radius of about 87.750 mm andintersects to the axis of revolution 12 at a fourth location 48 which islocated about 8.115 mm above the third location 44 where an extension ofthe internal surface 40 intersects the axis of revolution 12.

The system of lenses includes a first, upper lens 50 located within alower portion of the hole 28, a second, intermediate lens 52 locatedbelow the upper lens 50, and a third, lower lens 54 located below theintermediate lens 52. The upper lens 50 has a convex upper surface 56with a radius of about 18.000 mm and a lower surface with a radius ofabout 20.475 mm. The intermediate lens 52 has an upper, convex surface60 with a radius of about 6.060 mm and a lower, concave surface 62 witha radius of about 4.700 mm. The lower lens 54 has an upper, concavesurface 64 with a radius of about 10.550 mm and a lower, convex surface66 with a radius of about 5.325 mm. Other features of the upper,intermediate and lower lenses 50, 52 and 54 are not discussed further indetail herein as these features would be evident to one of ordinaryskill in the art.

In use, the light from a 360° surrounding panoramic scene enters thetransparent component 20 through the upper, convex surface 22. Light isreceived from the surrounding panoramic scene for an unbroken includedangle 72, in a vertical plane of the axis of revolution 12, extendingfrom an angle 74 which is located about 30° below the horizon to anangle 76 which is located about 30° above the horizon. By extending theupper, convex lens 22 or altering its shape, the angle 76 below thehorizon may be increased. When the light enters the transparentcomponent 20, the light is refracted slightly downwardly by the upper,convex surface 22, thus reducing the angle of the light with respect tovertical. The light then passes through the transparent component 20 andis then reflected upwardly by the reflective surface 38. Due to beconvex shape of the reflective surface 38, the angle of the light withrespect to vertical is further reduced after reflection from thereflective surface 38. The light then passes through the transparentcomponent 20 and exits the transparent component through the internalsurface 40. Due to the concave shape of the internal surface 40, thelight is refracted slightly upwardly when exiting the transparentcomponent 20 through the internal surface 40, thus further reducing theangle of the light with respect to vertical.

After leaving the transparent component, the light passes upwardlythrough the hole 28 and is reflected downwardly by the reflective area46 of the mirror 16. The light then passes downwardly through the hole28 and whereafter it is refracted respectively by the upper lens 50, theintermediate lens 52, and the lower lens 54. The light, after leavingthe lower lens 54, is focused by creating a flat image on a flat focalplane 78.

It can be seen from the a foregoing description that a simple, compactarrangement is provided which is capable of capturing a view of a 360°surrounding panoramic scene. In particular, the panoramic imagingarrangement 10 includes only five components namely the lens block 14,the mirror 16 and the upper, intermediate and lower lenses 50, 52 and54. Moreover, all the surfaces of the panoramic imaging arrangement 10which manipulate light are spherical or substantially spherical so as tobe easily manufacturable.

A final image is created which is corrected for image flatness andastigmatism. It could be noted that no particular surface or surfacescorrect for image flatness and astigmatism, but rather that the sizes,positioning and orientations of all the surfaces cooperate to produce afinal image which is corrected for image flatness and astigmatism. Ithas been found that the panoramic imaging arrangement 10 is particularlysuitable for creating a monochromatic image of the surrounding panoramicscene. One of ordinary skill in the art would appreciate that thepanoramic imaging arrangement 10 may be modified or may be complementedby additional lenses which would make it more suitable for capturingcolor images of a surrounding panoramic scene.

While certain exemplary embodiments have been described and shown in theaccompanying drawings, it is to be understood that such embodiments aremerely illustrative and not restrictive of the current invention, andthat this invention is not restricted to the specific constructions andarrangements shown and described, since modifications may occur to thoseordinarily skilled in the art.

What is claimed:
 1. A partial panoramic imaging arrangement comprising:a transparent component having: a first surface, about an axis ofrevolution, having a convex profile with a first curvature in a plane ofsaid axis of revolution; a second surface, about said axis ofrevolution, having a first concave profile with a second curvature insaid plane of said axis of revolution, said second surface beingsubstantially spherical; and an opening formed within the transparentcomponent to define a third internal surface, about said axis ofrevolution, having a second concave profile with a third curvature insaid plane of said axis of revolution, said first curvature being largerthan said third curvature; and a reflective material on said secondsurface to provide a reflective surface against said second surface;wherein said first surface and said reflective surface are positionedrelative to one another so that light, from a greater than 90 degreesurrounding partial panoramic scene, enters the transparent componentthrough said first surface, is reflected from said reflective surface,and leaves the transparent component through said third internalsurface.
 2. The arrangement of claim 1, wherein said first surface issubstantially spherical.
 3. The arrangement of claim 1, wherein saidgreater than 90 degree surrounding partial panoramic scene issubstantially a 360 degree panoramic scene.
 4. The arrangement of claim1, wherein said first surface and said reflective surface are located onopposing sides of the transparent component and said reflective surfacehas a convex profile in said plane of said axis of revolution.
 5. Thearrangement of claim 4, wherein at least extensions of said firstsurface and said reflective surface intersect.
 6. The arrangement ofclaim 1, wherein said light passes through a total of less than fivelenses after exiting the transparent component until being focused. 7.The arrangement of claim 6, wherein said light passes through a total ofthree lenses after exiting the transparent component until beingfocused.
 8. The arrangement of claim 1, further comprising a system oflenses positioned to receive said light after exiting the transparentcomponent, the system of lenses at least focusing said light into asubstantially flat plane.
 9. The arrangement of claim 8, furthercomprising a mirror which reflects said light after exiting thetransparent component, wherein a hole is formed through the transparentcomponent, the opening forming at least part of said hole, through whichsaid light at least partially passes after being reflected by the mirrorand before passing through the system of lenses.
 10. The arrangement ofclaim 9, wherein the mirror is curved.
 11. The arrangement of claim 10,wherein the mirror has a concave reflective area.
 12. A panoramic camerasystem comprising: an imaging arrangement comprising: a transparentcomponent having: a first surface, about an axis of revolution, having aconvex profile with a first curvature in a plane of said axis ofrevolution; a second surface, about said axis of revolution, having afirst concave profile with a second curvature in said plane of said axisof revolution, said second surface being substantially spherical; and anopening formed within the transparent component to define a thirdinternal surface, about said axis of revolution, having a second concaveprofile with a third curvature in said plane of said axis of revolution,said first curvature being larger than said third curvature; and areflective material on said second surface to provide a reflectivesurface against said second surface; wherein said first surface and saidreflective surface are positioned relative to one another so that light,from a greater than 90 degree surrounding partial panoramic scene,enters the transparent component through said first surface, isreflected from said reflective surface, and leaves the transparentcomponent through said third internal surface; and a camera, configuredto capture the light that leaves the transparent component.
 13. Thearrangement of claim 12, wherein said greater than 90 degree surroundingpartial panoramic scene is substantially a 360 degree panoramic scene.14. The arrangement of claim 12, wherein said camera is a video camera.15. The arrangement of claim 12, wherein said camera is a digitalcamera.
 16. The arrangement of claim 12, wherein said camera is a stillcamera.
 17. The arrangement of claim 12, wherein the panoramic camerasystem sends a portion of said surrounding partial panoramic scene to asurveillance system.
 18. The arrangement of claim 12, wherein thepanoramic camera system is attached to a moving object.
 19. Thearrangement of claim 18, wherein the moving object is a helmet.
 20. Thearrangement of claim 18, wherein the moving object is a vehicle.